Comparative research of COD degradation efficiency in humus media filters
几种腐殖填料生物滤池COD去除效能比较研究

Biofilters filled with aged refuse,peat,coal and sand were used to treat simulation wastewater in a lab-scale.To provide a theoretical basis for the filler modification,the COD removal efficiency and degradation characteristics of four biofilters were comparatively studied.SEM images showed that aged refuse and peat were constituted of reunion bodies with three-dimensional space structure.Coal and sand which had less rough surface mainly were made up of small particles.Three kinds of microorganism were found in all four biolfilters,which played a main function in the organic matter degradation process.In laboratory research,all the biofilters filled with aged refuse,peat and coal displayed ideal organic matter removal rates when inlet concentrations were 500 mg/L and 1 000 mg/L.In contrast to the other two biofilters(aged refuse and coal),the organic matter specific removal rate of biofilter filled with peat was lowest,and the hydraulic permeability coefficient was highest,which led to the minimum blockage.Biofilter filled with peat was most likely to run stably in long-term,and peat was proved to be excellent humus filler.